1. In 1803, the United States completed the Louisiana Purchase from France, which included what is now South Dakota. The purchase doubled the size of the country and opened up vast new territories for settlement and exploration.

2. On December 15, 1890, the Wounded Knee Massacre occurred near Pine Ridge, South Dakota. Approximately 150-300 Native American men, women, and children were killed by the U.S. Army, marking the tragic end of the Indian Wars in the region.

3. In 1960, the Oahe Dam on the Missouri River was completed. The dam, located near Pierre, South Dakota, provides hydroelectric power and irrigation to the region, as well as flood control and recreation opportunities.

4. On December 15, 1987, South Dakota Governor George Mickelson signed a law establishing the South Dakota Film Commission, which helped to promote the state as a location for film and television production.

5. In 2003, the Crazy Horse Memorial in the Black Hills of South Dakota celebrated its 50th anniversary. The massive sculpture, which depicts Lakota warrior Crazy Horse on horseback, is still under construction and will eventually be the largest mountain carving in the world.